The Coen brothers may just have made their masterpiece with this, their 14th feature and yet another hairpin-bend change of direction, which has been their trademark for their entire career.

Two films back they were prowling the Texas badlands in a gruesome tale of blood and revenge in No Country for Old Men; then they turned to weightless farce in the entertaining Burn After Reading.

Here they are heading to the suburbia of 1960s midwestern America for an elaborate, slippery, fable that feels, strange as it may sound, like a novel that Saul Bellow or Bernard Malamud never quite got around to writing.

A Serious Man starts off odd, and gets odder. The first five minutes is entirely in Yiddish, a Coen-ised version of a shtetl folk-horror tale featuring a bearded old man who may or may not be a dybbuk (wandering spirit). Suffice to say, the Coens don't muck about when it comes to the use of stabbing weapons.

Then we flip forward from the old country to the new world, to where our protagonist, Larry Gopnik (played by Michael Stuhlbarg) is your archetypal harassed and neurotic Jewish-American college professor.

His apparently unimpeachable lifestyle is crumbling rapidly: one of his students is trying to bribe his way through exams, his application for tenure is being undermined by ­ anonymous threatening letters, his deadbeat brother is sleeping on the sofa and attracting the attention of the police, and – this is the killer – his wife is planning to leave him for another man, one of those swinging middle-aged types who embraced the permissive culture with desperate fervency.

To offset this Gopnik goes looking for answers from his religion, but unlike Judah Rosenthal in Woody Allen's Crimes and Misdemeanors, he does not come up against the blank wall of a Godless universe; what he encounters are perplexing rabbis telling him baffling parables that just leave him feeling more and more confused.

It's this refusal to neatly resolve their narrative that gives A Serious Man its distinctive flavour; it has the same open-ended spirit of The Graduate, an authentic classic of late 60s Jewish-American culture. (A Serious Man could easily have been conceived as a sequel to that film, with Gopnik as a grown-up Benjamin Braddock.)

The Coens, though, don't quite do deeply felt alienation like anyone else. Despite the opaque story line, their film is a glittering, perfectly honed artifice; but what pushes it into the Coen premier league is the sense that, as with Fargo, there's something very personal going on here.

It's not autobiographical exactly, but the Minnesota setting is the Coens' own childhood universe, and they revved up for their barmitzvahs at pretty much the same time as Gopnik's son, Danny. The Coens, so normally elusive, have let the mask slip a bit. It's paid wonderful dividends.